Conventionally, when constructing a reinforced-concrete building, spacers in the form of cement blocks are used to space reinforcement rods from the shuttering frame for forming a floor slab of the building a distance thereby to enable the floor slab to have an optimal strength.
Also, indicators are used for workers to easily perceive what is the thickness that the floor slab is intended to obtain so that they can decide when to stop the pouring of the concrete slurry into the shuttering frame.
Since the conventional spacers and indicators are individual from each other, to lay them on the shuttering frame is very laborious. Furthermore, since the height of the conventional indicators cannot be easily adjusted, the conventional indicators cannot be easily adapted to different building conditions which respectively require a different thickness for the floor slab.
In view of the disadvantages of the prior art, the present inventor has invented a reinforced-concrete floor slab thickness indicator/reinforcement rod spacer combination 80 (as shown in FIG. 8) which combines the indicator and spacer into a single unit, wherein the combination 80 forms a prior art of the present invention.
Referring to FIG. 8, the combination 80 consists of an indicator 81 and a spacer 82 fixedly mounted on a base 89. The indicator 81 comprises an indicating portion 816, a threaded post 812 fixedly mounted on the base 89 and a first spring 814 connecting the indicating portion 816 and the threaded post 812 together. The first spring 814 can have a movement along the post 812 by rotating the first spring 814 about the post 812 so that the level of the indicating portion 816 may be adjusted to meet different building conditions.
The spacer 82 comprises a rod 83 fixedly connected to the base 89, a medial portion 85 slideably mounted on the rod 83, a second spring 84 has a first end seated on the base 89 and a second end supporting the medial portion 85, and a supporting portion 86 defining a reinforcement rod receiving recess 87, the supporting portion 86 being threadedly engaged with the medial portion 85. By rotating the supporting portion 86 about the medial portion 85, the level of the supporting portion 86 can be adjusted.
Although the above combination 80 which has a dual function to indicate the floor slab thickness and space the reinforcement rod from the shuttering frame a distance, is proved to be able to function well, it still has some disadvantages which need to be improved.
Among these disadvantages, the first is that to rotate the first spring 814 about the threaded post 812 to move the first spring 814 along the threaded post 812 is not convenient, and further causes the level of the indicating portion 816 to be not easily and quickly adjusted.
Furthermore, since the supporting portion 86 together with the medial portion 85 is only slideably supported on the relatively slim rod 83 by the second spring 84, the rigidity for supporting the medial and supporting portions 85, 86 is relatively poor, which results in that the reinforcement rod put on the supporting portion may not be able to be stabilized at its intended location. This situation becomes aggravated particularly when the flow of the concrete slurry poured onto the shuttering frame on which the combination 80 is laid has a violent current. If this situation happens, the reinforcement rod supported by the spacer 82 cannot be retained in its intended position, and, thus, the reinforced-concrete floor slab, which includes the reinforcement rod supported by the spacer 82 will not be able to obtain an optimal strength.
The present invention is disclosed to obviate/mitigate the above mentioned disadvantages of the conventional wooden shuttering frame.